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%I #5 Mar 31 2012 12:36:25
%S 83,1349,14831,68551,241221,680115,1686561,3665777,7197327,13441577,
%T 23509903,38130019,62475265,96810419,144798413,211419333,301429771,
%U 421198113,580071707,789348015,1055270897,1390678351,1808027465
%N Number of lower triangles of a 5X5 integer array with all row and column sums zero and all row and column sums of squares <= 2n^2
%C Row 5 of A195892
%H R. H. Hardin, <a href="/A195893/b195893.txt">Table of n, a(n) for n = 1..55</a>
%e Some solutions for n=4
%e ..0..........0..........0..........0..........0..........0..........0
%e ..3-3.......-3.3.......-3.3.......-2.2.......-1.1.......-4.4........1-1
%e .-2.4-2......0-2.2......4-3-1......3-3.0......3.1-4.....-1-1.2.....-4.3.1
%e .-2-2.0.4....3.1.0-4...-1.0.4-3....2.2.0-4...-1.0.2-1....3-1-4.2....2.2-1-3
%e ..1.1.2-4.0..0-2-2.4.0..0.0-3.3.0.-3-1.0.4.0.-1-2.2.1.0..2-2.2-2.0..1-4.0.3.0
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 24 2011
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